The present invention is related to systems and methods for encoding and decoding information, and more particularly to systems and methods for systematic block code encoding and decoding.
A number of encoding/decoding schemes have been developed to meet the needs for, among other things, data storage and data transmission. As one example, low-density parity-check (LDPC) codes have been developed that provide excellent error correcting performance using a highly parallelized decoding algorithm. However, while LDPC codes provide an appealing opportunity for applications demanding encoding and decoding functionality, the complexity of circuits implementing LDPC codes is often greater than the advantages of using LDPC codes. At least in part for this reason, encoding schemes relying on LDPC codes have found somewhat limited use.
Turning to FIG. 1, a typical transmission system 100 utilizing an LDPC encoder and a separate LDPC decoder is depicted. Transmission system 100 includes a transmission device 110 and a receiving device 160. Transmission device 110 includes an information source 120 that provides a stream of information to an LDPC encoder 130. LDPC encoder 130 encodes the received stream of information and provides an encoded data set to a transmitter 140. Transmitter 140 modulates the encoded data set to create a transmitted data set 150 that is provided to a receiver 190 of receiving device 160 via a channel 145. In various cases, errors are introduced to data set 150 by channel 145. Receiver 190 demodulates the encoded data set and provides it to an LDPC decoder 180 that decodes the encoded data set including an attempt to correct any introduced errors, and provides the decoded information as received information 170.
In general, the computational complexity required to encode using LDPC codes of system 100 is proportional to the square of the number of bits in the produced codeword. Thus, for codewords of any substantial length, the computational complexity involved in encoding and decoding using system 100 is prohibitive. Some approaches to LDPC encoding/decoding are realized such that computational complexity is more linear (i.e., computational complexity varies in proportion to the number of bits in the produced codeword). In such cases a dedicated encoder and a dedicated decoder are used. While this has reduced the computational complexity and made LDPC codes more attractive, the circuitry required to implement systems using such approaches is still substantial and in many cases prohibitive.
Hence, for at least the aforementioned reasons, there exists a need in the art for advanced systems and methods for encoding information and/or decoding encoded information.